"By overwhelming consensus, the scientific community agrees that climate change is real. Greenhouse gases have increased markedly as a result of human activities and now far exceed pre-industrial values."
So says Rajendra Pachauri, Chairman of the Intergovernmental Panel on Climate Change, of Geneva, Switzerland. His remarks bear a warning for each of us and for future generations as well. In a speech to the United Nations Summit on Climate Change in Sept., 2009, Pachauri said warming has already resulted "in an increase in the frequency, intensity and duration of floods, droughts and heat waves."
By year 2020 in Africa, he added, "between 75 and 250 million people are projected to be exposed to water stress due to climate change and in some countries yields from rain-fed agriculture could be reduced by up to 50%." One estimate by the Pentagon puts the number of climate refugees by mid-century at 750-million. What's more, if the planet continues to grow warmer "in the absence of mitigation policies," Pachauri says it could lead to:
# Possible elimination of the Greenland ice sheet and a resulting rise in sea level of about seven meters (23 feet) as well as the possible disappearance of sea ice generally by the latter part of this century. Other authorities note there is far more ice in the Antarctic than in Greenland that is in danger of melting.
# An increase in the frequency of heat waves and heavy precipitation.
# An increase in tropical cyclone intensity.
# A decrease in water resources due to climate change in semi-arid areas such as the western United States, southern Africa and northeastern Brazil.
# An increased risk of extinction for 20 to 30 percent of Earth's species.
Climate authorities say that the rise in sea levels from the melting ice sheets would flood seaboard cities and put hundreds of millions of refugees in motion seeking shelter in northerly climates to find relief from the heat.
Globally, the area affected by drought has been increasing since the 1970s. At the same time, precipitation has increased significantly in eastern parts of North and South America, northern Europe and northern and central Asia, whereas it declined in the Sahel, the Mediterranean, southern Africa and parts of south Asia, Pachauri says.